Wireless networks are becoming an increasingly significant part of the Internet landscape. A wireless network, in general terms, is a network in which wireless (and possibly mobile) users are connected into a larger network infrastructure by one or more wireless (i.e. non-wired) links at the network's edge. Many types of wireless networks exist including, for example, wide area networks (WANs), metropolitan area networks (MANs), local area networks (LANs), personal area networks (PANs), mesh networks, cellular wireless networks including wireless 3G networks or wireless 4G networks based on, for example, Worldwide Interoperability for Microwave Access (WiMAX) and Long-Term Evolution (LTE) communication standards, and so forth. A wireless network's classification depends on, among other things, the bit transmission rate and the geographical range over which data transmission is supported by the network.
At a high level of abstraction, wireless networks may be classified according to two criteria: (1) whether a packet transmitted via the wireless network crosses exactly one hop or multiple wireless hops, and (2) whether the wireless network includes infrastructure such as a base station. This classification scheme generally yields four types of wireless networks including (1) single-hop, infrastructure-based wireless networks which include a base station (e.g., an entity responsible for sending and receiving data to and from wireless host(s) associated with the base station) and in which all communication between the base station and a particular wireless host occurs over a single wireless hop, (2) single-hop, infrastructure-less wireless networks that do not include a base station and in which one of the nodes in the network may coordinate transmissions of the other nodes over a single hop, (3) multi-hop, infrastructure-based wireless networks which include a base station, but in which some wireless nodes may have to relay their communication through other wireless nodes (e.g. wireless mesh networks), and (4) multi-hop, infrastructure-less wireless networks that do not include a base station and in which nodes may have to relay messages among several other nodes in order to reach a destination. Infrastructure-less wireless networks may also be referred to as ad-hoc wireless networks.
As previously noted, in infrastructure-based networks, a base station may send and receive data between associated wireless host(s). Wireless LANs have become a particularly ubiquitous form of infrastructure-based wireless networks, with one particular class of standards emerging as the dominant form, the Institute of Electrical and Electronics Engineers (IEEE) 802.11 wireless LAN, also known as WiFi. Various IEEE 802.11 standards for wireless LAN technology exist, including 802.11b, 802.11a, and 802.11g and 802.11n, which share various characteristics such as use of the same medium access protocol and frame structure for their link layer frames. However, these various standards differ in the frequency ranges in which they operate and their respective data rates such that each standard offers advantages and disadvantages over the other standards.